Game on Axis

combinatorics, dfs and similar, dsu, graphs, implementation

Delicious Dessert

binary search, dsu, hashing, math, number theory, string suffix structures

Boris and His Amazing Haircut

constructive algorithms, data structures, dp, dsu, greedy, sortings

Koxia and Tree

combinatorics, dfs and similar, dp, dsu, math, probabilities, trees

Koxia and Game

constructive algorithms, data structures, dfs and similar, dsu, flows, games, graph matchings, graphs, implementation

Access Levels

bitmasks, dsu, flows, graph matchings

Doremy's Experimental Tree

brute force, constructive algorithms, dfs and similar, dsu, sortings, trees

Edge Queries

data structures, dfs and similar, dp, dsu, graphs, trees

Make It Connected

binary search, brute force, constructive algorithms, dsu, graphs, greedy, matrices, trees, two pointers

Tick, Tock

combinatorics, dfs and similar, dsu, graphs

Dangerous Laser Power

constructive algorithms, dsu, sortings

Connectivity Addicts

constructive algorithms, dsu, graphs, greedy, interactive, shortest paths, trees

Permutation Addicts

constructive algorithms, data structures, dfs and similar, dsu, graphs, trees

Phase Shift

dfs and similar, dsu, graphs, greedy, implementation, strings

Edge Split

brute force, constructive algorithms, dfs and similar, dsu, graphs, probabilities, trees

Jatayu's Balanced Bracket Sequence

data structures, dsu, graphs, greedy

Kingdom of Criticism

data structures, dsu

Imitating the Key Tree

combinatorics, dsu, trees

Cross Swapping

2-sat, data structures, dsu, greedy, matrices

XOR Tree

bitmasks, data structures, dfs and similar, dsu, greedy, trees

DFS Trees

dfs and similar, dsu, graphs, greedy, sortings, trees

Qpwoeirut and Vertices

binary search, data structures, dfs and similar, divide and conquer, dsu, greedy, trees

Split Into Two Sets

dfs and similar, dsu, graphs

Tree Recovery

brute force, constructive algorithms, dfs and similar, dsu, graphs, trees

Number of Groups

data structures, dfs and similar, dsu, graphs, greedy, sortings

ANDfinity

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Cute number

binary search, brute force, data structures, dsu, implementation, math

Sanae and Giant Robot

binary search, brute force, data structures, dsu, greedy, sortings

Permutation Weight (Easy Version)

constructive algorithms, dfs and similar, dsu

Unique Occurrences

data structures, dfs and similar, divide and conquer, dp, dsu, trees

Lenient Vertex Cover

dfs and similar, divide and conquer, dsu, graphs, trees

Replace With the Previous, Minimize

dsu, greedy, strings

Preorder

combinatorics, divide and conquer, dp, dsu, hashing, sortings, trees

Where is the Pizza?

data structures, dfs and similar, dsu, graphs, implementation, math

Narrow Components

brute force, data structures, dp, dsu, math, trees

AND-MEX Walk

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Words on Tree

2-sat, dfs and similar, dsu, graphs, trees

Air Reform

data structures, dfs and similar, divide and conquer, dsu, graphs, implementation, trees

Anonymity Is Important

binary search, brute force, data structures, dsu, greedy, sortings

Inversion Graph

data structures, dsu, graphs, math

Cars

2-sat, constructive algorithms, dfs and similar, dsu, graphs, greedy, sortings

Spanning Tree Queries

binary search, data structures, dfs and similar, dsu, graphs, greedy, math, sortings, trees

Groceries in Meteor Town

binary search, data structures, dsu, trees

MinOr Tree

bitmasks, dfs and similar, dsu, graphs, greedy

Replace the Numbers

constructive algorithms, data structures, dsu, implementation

Equal or Not Equal

constructive algorithms, dsu, implementation

Unusual Minesweeper

binary search, dfs and similar, dsu, greedy, sortings

Trader Problem

data structures, dsu, greedy, sortings

X(or)-mas Tree

bitmasks, dfs and similar, dsu, graphs, trees

Social Network

dsu, graphs, greedy, implementation, trees

The Number of Imposters

constructive algorithms, dfs and similar, dp, dsu, graphs

Hemose Shopping

constructive algorithms, dsu, math, sortings

Labyrinth

binary search, dsu, greedy

Building Forest Trails

data structures, dsu

Jeopardy of Dropped Balls

binary search, brute force, dsu, implementation

Occurrences

combinatorics, dfs and similar, dp, dsu, fft, graphs

One-Four Overload

2-sat, constructive algorithms, dfs and similar, dsu, graphs, implementation

Mocha and Diana (Hard Version)

brute force, constructive algorithms, dfs and similar, dsu, graphs, greedy, trees, two pointers

Mocha and Diana (Easy Version)

brute force, constructive algorithms, dsu, graphs, greedy, trees

Gates to Another World

bitmasks, data structures, dsu, two pointers

Good Graph

data structures, dsu, graphs, trees

Common Divisor Graph

brute force, constructive algorithms, dsu, graphs, hashing, math, number theory

Permutation Shift

brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math

Jumping Around

binary search, data structures, divide and conquer, dp, dsu, graphs, shortest paths

Figure Fixing

constructive algorithms, dfs and similar, dsu, graphs, greedy, math

Little Alawn's Puzzle

combinatorics, dp, dsu, graphs, math

Nastia Plays with a Tree

constructive algorithms, data structures, dfs and similar, dp, dsu, greedy, implementation, trees

Phoenix and Earthquake

constructive algorithms, dfs and similar, dsu, graphs, greedy, trees

GCD and MST

constructive algorithms, dsu, graphs, greedy, number theory, sortings

Complete the MST

bitmasks, brute force, data structures, dfs and similar, dsu, graphs, greedy, trees

Dogeforces

constructive algorithms, data structures, dfs and similar, divide and conquer, dsu, greedy, sortings, trees

Playlist

data structures, dsu, implementation, shortest paths

Journey

dfs and similar, dp, dsu, implementation

Road Reform

dsu, graphs, greedy

Bakery

data structures, dsu

Euclid's nightmare

bitmasks, dfs and similar, dsu, graphs, greedy, math, sortings

Plan of Lectures

constructive algorithms, dfs and similar, dsu, graphs, implementation, sortings, trees

Team-Building

data structures, dfs and similar, dsu, graphs

Identify the Operations

combinatorics, data structures, dsu, greedy, implementation

A Convex Game

dsu, games

Virus

data structures, divide and conquer, dsu, graphs

Rain of Fire

binary search, data structures, dfs and similar, dsu, graphs, implementation

Graph and Queries

data structures, dsu, graphs, implementation, trees

Peaceful Rooks

dfs and similar, dsu, graphs

Clusterization Counting

combinatorics, dp, dsu, fft, graphs, trees

Avoid Rainbow Cycles

data structures, dsu, graphs, greedy, sortings, trees

Fancy Fence

*special problem, data structures, dsu, implementation, math, sortings

Mercenaries

bitmasks, brute force, combinatorics, dp, dsu, math, two pointers

Joker

*special problem, bitmasks, data structures, divide and conquer, dsu

Columns Swaps

2-sat, dfs and similar, dsu, graphs, implementation

String Transformation 1

dsu, graphs, greedy, sortings, strings, trees, two pointers

Merging Towers

data structures, dsu, implementation, trees

Odd-Even Subsequence

binary search, dp, dsu, greedy, implementation

Solve The Maze

constructive algorithms, dfs and similar, dsu, graphs, greedy, implementation, shortest paths

Johnny and Megan's Necklace

binary search, bitmasks, constructive algorithms, dfs and similar, dsu, graphs

Monopole Magnets

constructive algorithms, dfs and similar, dsu, graphs

Robots on a Grid

data structures, dfs and similar, dsu, graphs, greedy, matrices

K-Complete Word

dfs and similar, dsu, greedy, implementation, strings

Cow and Vacation

dfs and similar, dsu, trees

Kuroni and Antihype

bitmasks, brute force, dp, dsu, graphs